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Bitten by a venomous snake? There's hope! French scientist Albert Calmette developed the first snake antivenom in the late 1890s, and did such a good job that we use his technique to this day. Antivenom works by stimulating the production of antibodies which can smother venom's toxic effects, preventing spread and rendering them harmless. But how do you make it? Well, stay tuned to this episode of SciShow to find out.

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Bitten by a venomous snake? Well, you probably shouldn't waste three precious minutes watching this video, but if you're going to do it anyway, I can tell you that there is hope.

Some animals have a natural resistance to snake venom, like the snake-eating honey badger, which can be bitten in the face by a cobra an still not care. But for people, historically, you just had two choices: you could either just hope you'd recover, or you could just die. A lot of the time, you did both.

But all that changed with Albert Calmette. French researcher, dedicated public health advocate, and co-creator of the Tuberculosis vaccine. Calmette also developed the first snake antivenom in the late 1890s.
The story goes that Calmette was sent to Saigon in what is now Vietnam by his mentor Louis Pasteur--one of the fathers of microbiology--to help inoculate people against Smallpox and Rabies. One day, a major flood swept through his village, flushing up a bunch of monocled cobras that started biting everyone. But Calmette was like, 'Uh-uh, snakes!' And being an expert in the business of vaccine-making, he whipped up an antivenom called Calmette's Serum. His technique was so solid that it remains largely unchanged today.

Antivenom works by stimulating the production of antibodies, the highly specialized warrior proteins released by your immune system to neutralize dangerous antigens like viruses, bacteria, or--in this case--venom. Antivenom can't destroy a venom's toxins or reverse its ill effects, but the antibodies they create can smother them, preventing further spread and rendering them harmless.

And here's how you make it:

Step 1: Get Some Venom
To make antivenom, you need venom. And if you're wondering about the name, yes, you can also call it antivenin, if you want to. "Venin" is actually the French word, and since he was French, that's what it was originally called, but a while back, the World Health Organization decided that, in English at least, "antivenom" made a lot more sense.
Anyway, to make an antidote for venom, you need a lot of it. So, once you got your bag of deadly snakes, grab one, open its mouth over a vial, and gently squeeze its venom glands until they're empty. You'll only get a little bit at a time, so multiple snakes must be milked, as they call it, many times to get enough venom. Fun!
For example, in 1965, the National Institutes of Health told famed snake wrangler Bill Haast to collect about half a liter of coral snake venom. It took him 69,000 milkings over a three-year period to reach that goal.

Step 2: Freeze the Venom
Once the snake is milked, the venom is freeze dried to concentrate and preserve it.

Step 3: Use Some Other Animal to Make Antibodies
Find a horse, sheep, or goat and inject them with little doses of venom again and again over several weeks. This allows the animal to build antibodies and fight off the venom. The antibodies peak after a couple of months, at which point they can be harvested, by which I mean that up to six liters of blood is drained from the animal's jugular.
But don't worry, the animal isn't bled to death. It'll live on to enjoy the process all over again.

Step 4: Purify, Concentrate, and Deliver
After the bloodletting is done, you filter out the antibodies and then purify and concentrate them into dose vials. If you need it, like, right now, then good. But if you're just going to store it up for the next snake-handling encounter, then stash it in the freezer.
The fact that antivenom must be kept cold poses a serious problem for developing countries with scarce electricity. Unfortunately, those tend to be the same places that are inundated with killer snakes.

You've probably noticed by now that this whole process isn't easy. Making antivenom is expensive and time-consuming, which is one reason why it suffers global supply shortages all the time. A single vial may cost over $1,500 and a victim may require twenty to thirty vials to fully recover from a serious bite.
But, there are other ways. Remember Bill Haast and his half-liter of snake spit? He practiced a form of mithridatism, the process of making yourself immune to a toxin by gradually taking non-lethal amounts. He milked 100 snakes a day with his bare hands, and made his own decidedly lower-tech antivenom, leaving the horses out of it and using his own body. He pretty much single-handedly saved 21 snakebite victims by flying around the world, donating transfusions of his own blood.
He lived to be 100 years old, surviving 172 snake bites, and only losing one finger. To which I say, "Dang!"

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